# Assessing the COVID-19 legacy on hand hygiene: Retrospective observational before–after study of compliance and alcohol-based

## TL;DR

This study examines how hand hygiene practices changed before and after the COVID-19 pandemic in hospital ICUs, finding partial improvements that varied by unit and task.

## Contribution

The study provides empirical evidence on the sustainability of hand hygiene improvements post-pandemic and identifies contextual variations in compliance.

## Key findings

- Hand hygiene compliance increased from 61% pre-pandemic to 66% post-pandemic.
- Alcohol-based hand rub use increased more than fourfold after the pandemic.
- Compliance remained lowest before patient contact and aseptic procedures in adult and pediatric ICUs.

## Abstract

In the context of multidrug-resistant organisms and following the coronavirus disease 2019 (COVID-19) pandemic, preventing healthcare-associated infections (HAIs) remains a major global public health priority. Although hand hygiene (HH) adherence increased markedly during the acute phase of the pandemic, there is limited empirical evidence on the sustainability and contextual variability of these behaviors once emergency conditions subside and routine clinical practice resumes. We conducted a retrospective observational before-and-after study to evaluate hand hygiene compliance (HHC) and HH product use among healthcare professionals working in adult, pediatric, and neonatal intensive care units (ICUs) of a teaching hospital, comparing pre-pandemic (09/01/2017–08/01/2018) and extended post-pandemic (10/29/2021–12/27/2024) periods. In the post-pandemic period, we also examined adherence across the World Health Organization’s “Five Moments for Hand Hygiene.” A total of 2,789 HH opportunities were recorded (1,048 pre-pandemic and 1,741 post-pandemic). Overall compliance increased from 61% before the pandemic to 66% in the post-pandemic period (p = 0.004). Compliance remained lowest during moments preceding patient contact and aseptic procedures, particularly in adult and pediatric ICUs, while the neonatal ICU consistently demonstrated higher performance. In parallel, HH practices shifted substantially, with alcohol-based hand rub use increasing more than fourfold compared with the pre-pandemic period (OR 4.30; 95% CI 3.32–5.58; p < 0.001). These findings indicate that crisis-driven improvements in HH were only partially sustained after the COVID-19 pandemic and varied across clinical contexts and HH moments. This variability underscores the need for continuous, context-sensitive infection-prevention strategies to support durable HH compliance beyond emergency situations.